diff --git a/compiler/rustc_codegen_llvm/src/llvm_util.rs b/compiler/rustc_codegen_llvm/src/llvm_util.rs index bc3a94a4027..c9f5dd0f2c6 100644 --- a/compiler/rustc_codegen_llvm/src/llvm_util.rs +++ b/compiler/rustc_codegen_llvm/src/llvm_util.rs @@ -292,30 +292,33 @@ fn llvm_target_features(tm: &llvm::TargetMachine) -> Vec<(&str, &str)> { } fn print_target_features(sess: &Session, tm: &llvm::TargetMachine) { - let mut target_features = llvm_target_features(tm); + let mut llvm_target_features = llvm_target_features(tm); + let mut known_llvm_target_features = FxHashSet::<&'static str>::default(); let mut rustc_target_features = supported_target_features(sess) .iter() - .filter_map(|(feature, _gate)| { - for llvm_feature in to_llvm_features(sess, *feature) { + .map(|(feature, _gate)| { + let desc = if let Some(llvm_feature) = to_llvm_features(sess, *feature).first() { // LLVM asserts that these are sorted. LLVM and Rust both use byte comparison for these strings. - match target_features.binary_search_by_key(&llvm_feature, |(f, _d)| f).ok().map( - |index| { - let (_f, desc) = target_features.remove(index); - (*feature, desc) - }, - ) { - Some(v) => return Some(v), - None => {} + match llvm_target_features.binary_search_by_key(&llvm_feature, |(f, _d)| f).ok() { + Some(index) => { + known_llvm_target_features.insert(llvm_feature); + llvm_target_features[index].1 + } + None => "", } - } - None + } else { + "" + }; + (*feature, desc) }) .collect::>(); rustc_target_features.extend_from_slice(&[( "crt-static", "Enables C Run-time Libraries to be statically linked", )]); - let max_feature_len = target_features + llvm_target_features.retain(|(f, _d)| !known_llvm_target_features.contains(f)); + + let max_feature_len = llvm_target_features .iter() .chain(rustc_target_features.iter()) .map(|(feature, _desc)| feature.len()) @@ -327,10 +330,10 @@ fn print_target_features(sess: &Session, tm: &llvm::TargetMachine) { println!(" {1:0$} - {2}.", max_feature_len, feature, desc); } println!("\nCode-generation features supported by LLVM for this target:"); - for (feature, desc) in &target_features { + for (feature, desc) in &llvm_target_features { println!(" {1:0$} - {2}.", max_feature_len, feature, desc); } - if target_features.is_empty() { + if llvm_target_features.is_empty() { println!(" Target features listing is not supported by this LLVM version."); } println!("\nUse +feature to enable a feature, or -feature to disable it.");